Step 3: Look at the Sanborn Key Map
- Find the Key Map(s) for the volume(s) you are interested in.
- The key maps & indices for the available digital Chicago sets have been compiled in pdf format.
- Once again, locate the major intersections near the address.
- Note the sheet number you will need. Also note the surrounding sheet numbers just in case the location is close to the edge of the sheet.
Step 3: Example
James finds the intersection of Harrison and Halsted but that doesn’t narrow his search down to a single sheet. From there, he locates the intersection of Taylor and Morgan. It looks like he will need to find Sheet 79 or 63 since the address is just north of the intersection. James takes note of the sheets surround Sheet 79: 63 to the north, 62 to the northwest, 78 to the west, 95 to the south, and 80 to the east. This way, he won’t have to revisit the key if Sheet 79 is not the sheet he was looking for.
